Lock attachment



JOHN M. WILSON, OF PHILADELPHIA, PENNSYLVANIA.

LOCK ATTACHMENT.

Specification of Letters Patent No. 24,346, dated June 7, 1859.

To all whom 'it may concern:

Be it known that I, JOHN M. WILSON, of

Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a new and Improved Safety Attachment fo-r Locks; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making a part of this specification, in which- Figure l, is a face view of my invention applied to a lock, the front side of the casing being removed. ,Fig 2, is a transverse section of ditto, applied to a door, m, Fig. l, shows the plane of section.

Similar letters of' reference indicate corresponding parts in the two figures.

The nature of my invention consists in the within specified peculiar arrangement of parts, in combination with an ordinary lock, in the manner hereinafter described; this arrangement preventing the lock being picked and also preventing access to the working parts of the lock so that impressions in wax cannot be taken with a view of constructing keys to fit the lock.

To enable those skilled in the art to fully understand and construct my invention I will proceed to describe it.

A, represents a case lock which may be of ordinary construct-ion and applied to the door B, in the usual way.

C, is a box or case which is attached to the inner side of t-he lock case and is fitted within a recess in the door to admit of the lock A being fitted snugly against the inner side of the door, as shown plainly in Fig. 2.

The box C, is not necessarily as large as the lock case, and it is fitted over the key hole a, at the inner side of the lock case, the adjoining side of the box C, having a key hole b, made in it to correspond and register with the hole a, as shown in Fig. 2. In the opposite side of the box C, a key hole c, is made in a reverse position to the hole b, and a hole (Z, is made in the door B, said hole being in line with the key hole 0, but formed so as to be in a reverse position to the hole c, the latter being inverted, and of a different form from a, b, so that a key that would enter c, would not necessarily pass through 0;, b.

Within the box C, and surrounding its key holes c, there are wards c, said wards V being attached to the inner sides of the front and back plates of the box C, and so ar'-, ranged as to fit recesses f, in the front and back edges of the bit g, of the key D, see Fig. 2, in which the key is shown fitted in the box C, in red. v Y

E, is la guard which is formed by bending a metal plate in the shape of the key bit g, so as to form a sort of socket to receive the bit. This guard E, is fitted between the wards e, at each side of the box C', and is allowed to rotate freely between the wards, serving as guides to the guard. A plate F, is also secured within the box C, said plate having a circular opening at its center in which the guard E, is allowed to turn or rotate, the inner edge of the plate fitting in the end of the guard and serving as a guide for the same, as shown clearly in Fig. 2.

To the upper and lower part of the inner plate of the box C, stops G, G, are attached by pivots It. -These stops are formed of plates having each a recess z', formed in their inner edges, or the edges which face each other, said recesses being sufficiently large to receive the end of the key bit g. The recesses c', z', are in line with the key holes b, c, as shown clearly in Fig. l. Within the box C, springs H H are placed, which bear on the stops G, Gr, and have a tendency to keep their recesses z', i, in line with the key holes b, c. This will be fully understood by referring to Fig. 1.

The operation is as follows z-Suppose the door tol be in a locked state, to unlock it, the key is passed through the hole d, the bit g, being in an inverted position so that it may pass through the hole c, and into the guard E, within the box C. The key D, is then turned until the end of the guard E, fits in the recess z', of the lower stop G, which retains the guard or prevents it from casually moving. The guard E, while in this position is in line with the key holes a, b, and the key is shoved into the lock A, and then turned as usual so as to throw back its bolt. The key bit g, is then withdrawn from the -lock A, into the box C, and within the guard E, and the key turned until the guard is caught by the recess 11, of the uppei` stop Gr, the guard and key bit being then in line with the holes c, d, so that the key may be withdrawn. The same operation is performed in locking the door.

From the above description it will be seen that the lock cannot be picked at the outer side of the door for the holes c and a, b, are not in line with `each other and'Y picks cannot be 1ntroduced,-or the sameV reason impressions of the parts of the look A, cannot be obtained. Neither can the look be opened by fitting a key to it, for a key cannot be fitted to the lock owing to the inner holes a b being out of sight of theV operator and of a different form from key hole c, he has noY clue therefore whereby to form a bit. The guard E, serves also to obscure the holes a, b, and prevent the inser tion of picks and other implements.

I do not claim separately the placing of two key holes out of line with each other, in order that the key may be turned before entering the lock proper, as' 'many locks have been devised embracing such arrangement;

JOHN M. VILSON.

Witnesses:

C. BRAZER, GEO. R. NAGEL. 

